Whedon is in negotiations to write, direct and produce a Batgirl stand-alone movie for Warner Bros., adding another heroine to the studio's DC cinematic universe.

Warner Bros. Pictures president Toby Emmerich will oversee the project, along with Jon Berg and Geoff Johns.

The most popular iteration of Batgirl was introduced in 1967 as Barbra Gordon, the daughter of Gotham City police commissioner and frequent Batman foil James Gordon. She often aligns herself with Batman, Robin and Nightwing/Dick Grayson.

Batgirl will be the second female superhero stand-alone in Warner Bros. DCU (Wonder Woman is set to hit theaters June 2). Whedon has long been credited as a pioneering voice for female-focused genre fare, having created the hit TV show Buffy the Vampire Slayer two decades ago.

Whedon's most notable comic book movie work has been with Marvel, having written and directed The Avengers and Age of Ultron for Disney. Batgirl will mark a return (of sorts) to DC movies for the director, who previously worked on Wonder Woman scripts in the early 2000s that never got off the ground.

The Batgirl character was memorably played by the late Yvonne Craig on the third and final season of ABC's Batman in 1967-68. In Joel Schumacher's Batman & Robin (1997), Alicia Silverstone played Batgirl opposite George Clooney's Batman.

A more recent comic book run of Batgirl, Batgirl of Burnside, has updated the Gordon's storyline, moving her into the Gotham borough of Burnside (a pseudo-Brooklyn) as a doctoral student that fights crime after working on her thesis at hipster coffee shops.